Method for managing viewing of a particular content recorded on an information recording medium

ABSTRACT

A DVD player  11  reads disc control information recorded on a DVD medium M and causes a display  12  to display a start menu screen, thereby prompting a viewer to perform authentication ( 1 ). The viewer uses a remote controller  11   a  to display a first viewer authentication screen ( 2 ). Then, an acquisition code is indicated and an input of a password is requested. Here, the viewer uses a mobile telephone  13  to access the website indicated by an URL shown on the first viewer authentication screen (substantially, a server computer  2 ) and inputs a user ID and an acquisition code, thereby acquiring a password required for viewing the content of the DVD medium M (( 3 ) and ( 4 )). The viewer inputs the acquired password into the first viewer authentication screen ( 5 ). While a program recorded on the DVD medium M is executed, the DVD player  11  authenticates the password which has been input. If the password is judged to be valid, reproduction of the specified content is started.

CROSS-REFERENCES BACKGROUND

The present invention relates to a viewing management method of aspecified content recorded on an information recording medium such as aDVD.

DVD is a high capacity recording medium (media) that is currentlybecoming mainstream, and is used for recording audio/visual contentsdata such as computer programs and movies. A DVD-ROM is a playback-onlydisk, and DVD-Video and DVD-Audio are prescribed as the applicationformats thereof. A DVD-Video is a video format prescribed for use inrecording audio/visual contents.

In addition to being able to record contents data such as actual imagesand sounds, a DVD-Video is able to record control information forrealizing the viewing regulation function or special reproductionfunction. For example, with parental reproduction, which is one of theviewing regulation functions, a parental level is set according to agein consideration of the nature of the content. Further, DVD-Video isprescribed with a region code showing the areas where such content canbe reproduced, and reproduction is permitted only when the region codesof the drive device, video reproduction device (player) and media allcoincide.

SUMMARY

As described above, although the DVD-Video is prescribed with variousviewing regulation functions in terms of specification, from theperspective of media providers providing DVD media to users, this wasnot necessarily sufficient upon engaging in more detailed viewingregulations or viewing management (hereinafter simply referred to as“viewing management”). For example, there were requests from mediaproviders for setting a time limit for viewing the contents, or enablingviewing management by performing user authentication prior to thereproduction of the content, and requests for enabling the charge inassociation with this user authentication.

As one technology for realizing this kind of detailed viewingmanagement, for example, “DVD MAGIC” proposed by the applicant is known.This DVD MAGIC “locks” the DVD media to be distributed to the users,and, upon reproduction, the user acquires a key from the mediaprovider's site on the Internet and unlocks the DVD media to enablereproduction. According to this DVD MAGIC, since the user will accessthe media provider's site upon reproduction of the DVD media, there is amerit in that the media provider will be able to lead users to contentsother than the intended content naturally, and supplement the users'viewing activities. For example, the gazette of Japanese PatentLaid-Open Publication No. 2002-218405 discloses an example employingthis DVD MAGIC.

Nevertheless, this DVD MAGIC was originally developed based on personalcomputers, and general DVD players currently on the market were not ableto realize the mechanism or function for performing a more detailedviewing management as with DVD MAGIC. Meanwhile, to newly incorporate ascheme for performing viewing management in general DVD players isunrealistic when considering the compatibility with many of the DVDplayers on the market, and there are restrictions of giving utmostconcern to the specification.

Thus, an object of the present invention is to provide a viewingmanagement function in a simple manner while giving consideration to thecompatibility with existing visual reproduction devices.

The gist of the present invention is a viewing management method formanaging the viewing of a content recorded on an information recordingmedium readable/reproducible with a prescribed reproduction device,wherein an acquisition code prerecorded on an information recordingmedium is presented to a viewer wishing to view a viewing managementtarget content, the viewer is urged to enter the password,authentication is performed regarding the password input and acquired bythe viewer from a server computer based on the presented acquisitioncode, and, when it is judged that the password is valid as a result ofthe authentication, the reproduction of the viewing management targetcontent is started.

Here, it is preferable that the viewer uses an information terminaldevice such as a mobile telephone to access the server computer, and toacquire the password in exchange for the acquisition code. Moreover,when the viewer acquires the password from the server computer, it isdesirable to charge the viewing fee of the viewing management target tothe viewer.

More specifically, the present invention according to the firstperspective for achieving the foregoing object is a viewing managementmethod for managing the viewing of a content recorded on an informationrecording medium readable with a prescribed reproduction device,comprising: a step of the prescribed reproduction device that startedreading the information recording medium presenting a prescribedacquisition code to a viewer, and urging the viewer to input aprescribed password; a step of a prescribed server computer accessed bythe information terminal device of the viewer according to prescribedposition information urging the viewer to input the prescribedacquisition code; a step of the prescribed server computer presenting apassword corresponding to the prescribed acquisition code to the viewerupon receiving the prescribed acquisition code from the informationterminal device of the viewer; a step of the prescribed reproductiondevice performing authentication based on the received prescribedpassword upon receiving the prescribed password from the viewer; and astep of the prescribed reproduction device starting the reproduction ofthe content recorded on the information recording medium when it judgesthat the received prescribed password is valid.

Here, it is preferable that a password management table associating thepassword with the prescribed acquisition code is recorded on theinformation recording medium, and the prescribed reproduction devicepresents a prescribed acquisition code corresponding to the randomnumber generated according to a prescribed random function.

Further, it is preferable that the server computer comprises a viewingmanagement database containing a table corresponding to the passwordmanagement table, and by referring to the viewing management database, aprescribed password corresponding to the prescribed acquisition codereceived from the information terminal device of the viewer isspecified, and presented to the viewer.

Moreover, it is preferable that prescribed position information isrecorded on the information recording medium, and the prescribedreproduction device presents the prescribed acquisition code togetherwith the prescribed position information.

Further, it is preferable that the viewing management method furthercomprises a step of urging the viewer to select a viewing managementtarget content before presenting the acquisition code, and when theviewing management target content is selected, the prescribedacquisition code corresponding to the selected viewing management targetcontent is presented.

Moreover, the present invention according to the second perspective isan information recording medium readable with a prescribed reproductiondevice, wherein the information recording medium is used for recording aviewing management target content, a prescribed password managementtable and prescribed control information, a prescribed password isassociated with a prescribed acquisition code in the prescribed passwordmanagement table, and the prescribed control information causes theprescribed reproduction device to realize: a function of presenting theprescribed acquisition code to the viewer and urging the viewer to inputthe prescribed password, a function of, when the viewer inputs theprescribed password, performing authentication of the input prescribedpassword, and a function of reproducing the viewing management targetcontent according to the result of the authentication.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram for explaining the viewer management system forrealizing the viewing management method according to an embodiment ofthe present invention;

FIG. 2 is a flowchart for explaining the flow of operation of the DVDplayer 11 according to an embodiment of the present invention;

FIG. 3 is a diagram showing an example of the activation menu screenaccording to an embodiment of the present invention;

FIG. 4 is a diagram showing an example of the first viewerauthentication screen according to an embodiment of the presentinvention;

FIG. 5 is a diagram for explaining the password management tableaccording to an embodiment of the present invention;

FIG. 6 is a flowchart for explaining the flow of password acquisitionprocessing according to an embodiment of the present invention;

FIG. 7 is a diagram showing an example of the second viewerauthentication screen according to an embodiment of the presentinvention;

FIG. 8 is a diagram showing an example of the acquisition code inputscreen according to an embodiment of the present invention;

FIG. 9 is a diagram for explaining an example of the data structure ofthe viewing management database according to an embodiment of thepresent invention;

FIG. 10 is a diagram showing an example of the viewing confirmationscreen according to an embodiment of the present invention; and

FIG. 11 is a diagram showing an example of the password presentationscreen according to an embodiment of the present invention.

DETAILED DESCRIPTION

Next, the embodiments of the present invention are now explained withreference to the drawings. In the following embodiment, although anexplanation is made employing a DVD media, there is no particularlimitation, and the present invention can also be employed in othermedias such as CD-ROMs or next-generation media.

FIG. 1 is a diagram for explaining the viewer management system forrealizing the viewing management method according to the presentembodiment. As shown in FIG. 1, this system is constituted from a viewersystem 1 on the viewer side for viewing the content recorded on a DVDmedia M, and a server computer 2 on the media provider side fordistributing/providing the DVD media M to the viewer. The DVD media Mhas various settings for realizing the viewing management methodaccording to the present embodiment.

Specifically, this DVD media M is processed in advance during theproduction/manufacture process to enable the reproduction of contentsonly via a prescribed menu to prevent the viewing management targetcontent from being directly reproduced. Control of this kind ofreproduction, for example, is able to employ the user operation control(UOP) under the DVD specification, and a setting of prohibiting therespective items of “chapter play”, “skip play” and “time designationplay” against the program chain (PGC) can be made. Further, directaccess to content data from computers and the like will be prohibited.The DVD media M subject to such settings will be able to reproducecontents only via a specified menu.

A viewer system 1 is typically constituted from a DVD player 11 forreproducing the DVD media M according to the DVD-Video, a display device12 for outputting the signal reproduced with the DVD player 11 as imagesand sounds, and an information terminal device 13 owned by the viewer.

The DVD player 11 is equipped with a remote controller 11 a as the userinterface, and an interactive operating environment is provided to theviewer thereby. As a result of the viewer operating the remotecontroller 11 a in relation to the visual contents displayed on thedisplay device 12, such viewer is able to provide various instructionsto the DVD player 11. However, the operation panel provided to the bodyof the DVD player 11 may be used instead of the remote controller 11 a.

The information terminal device 13 typically corresponds to a mobiletelephone capable of wireless communication, but another device may alsobe employed. For example, a general telephone capable of emitting a tonesignal or a set top box having an interactive function in a digitaltelevision service may also be employed. Below, a mobile telephone asthe information terminal device 13 will be explained as the example. Themobile telephone 13, in addition to an ordinary wireless telephonefunction, comprises an email function and Internet connection function.Typically, the mobile telephone 13 is able to exchange emails with anode (e.g., server computer 2) on the Internet via a gateway from awireless telephone network, and access websites.

The server computer 2 assumes the core role for realizing the viewermanagement method according to the present embodiment. The servercomputer 2 performs member authentication processing and viewingmanagement processing to the viewer using the DVD media M. In order toperform such member authentication processing and viewing managementprocessing, the server computer 2 comprises a database systemcorresponding thereto, and is organically linking such processes anddatabase system. The detailed operation processing of the servercomputer 2 will be described later.

In the viewer management system constituted as described above, theschematic explanation of the processing flow of the viewer managementmethod according to the present embodiment is as follows.

Incidentally, in addition to the foregoing reproduction regulationsetting being made to the DVD media M employed in the viewer managementmethod according to the present embodiment, programs and data fordynamically generating passwords and acquisition codes are alsoprestored in a prescribed area thereof. Special processing to beperformed in this kind of DVD media M may be conducted with theauthoring process during the manufacture of the DVD media.

Foremost, as shown in FIG. 1, when the viewer inserts the DVD media Minto the DVD player 11, the DVD player 11 reads the disc controlinformation recorded on the DVD media M, and displays the activationmenu screen according to such disc control information on the displaydevice 12 ((1) in FIG. 1). This activation menu screen is constitutedincluding with menu items for the media provider to requestauthentication to the viewer regarding the viewing management targetcontent.

The viewer uses the remote controller 11 a to conduct an interactiveoperation to the presented activation menu screen so as to display aviewer authentication screen on the DVD player side (hereinafterreferred to as the “first viewer authentication screen”) ((2) in FIG.1). In this first viewer authentication screen, the viewer is shown anacquisition code, and is requested to input a corresponding password.This acquisition code is set to have different contents each time theviewer makes a content reproduction request. As a result, even in caseswhere a plurality of viewing management target contents recorded on theDVD media M, a different acquisition code for each reproduction requestis presented to the respective contents, and the input of a differentpassword for each case can be requested.

Here, as the result of the viewer accessing the server computer 2 fromthe mobile telephone 13 and providing the acquisition code, such viewerwill be able to acquire a password in exchange therefor. In other words,the viewer uses the mobile telephone 13 to access the website(substantially the server computer 2) indicated by a URL shown on thefirst viewer authentication screen, inputs the user ID and password aswell as the acquisition code shown on the first viewer authenticationscreen, and acquires the password required for viewing the content ofDVD media M ((3) and (4) in FIG. 1). Incidentally, here, the viewer isregistered in the server computer 2 as a member, and has previouslyacquired a prescribed user ID and password.

As described above, the viewer acquires the password from the servercomputer 2, and inputs the acquired password in the first viewerauthentication screen ((5) of FIG. 1). And, the DVD player 11 performsauthentication regarding the input password under the execution of theprogram recorded on the DVD media M, and, when it is judged that suchpassword is valid, it starts the reproduction of the designated content.

Incidentally, when the DVD player 11 succeeds in the authenticationregarding the input password, it is preferable that a flag to sucheffect is stored in the internal memory buffer, and such flag remainseffective until the DVD media M is ejected.

As described above, in the present embodiment, upon reproducing aspecified content recorded on a DVD media M, the viewer uses the mobiletelephone 13 to access the server computer 2 on the Internet and acquirethe password with the acquisition code shown on the first viewerauthentication screen, and is urged to input such password. Thus, evenif it is a stand-along DVD player 11 that does not have a networkconnection function, it is possible to manage the viewing of contents.

FIG. 2 is a flowchart for explaining the operation flow of the DVDplayer 11 according to the present embodiment. Incidentally, althoughthe operation flow is explained sequentially for the sake of conveniencebelow, this is not limited thereto. Therefore, so as long as there is nocontradiction with the operation, the processing order may be rearrangedor performed in parallel.

In FIG. 2, when the viewer loads the DVD media M into the disc tray ofthe DVD player 11, the DVD player 11 loads the DVD media M in itsinternal disc reproduction mechanism, reads the disc control information(STEP 201), displays the activation menu screen according to such disccontrol information on the display device 12, and requests the viewer toselect the content to be reproduced (STEP 202).

FIG. 3 is a diagram showing an example of the activation menu screenaccording to the present invention. In this activation menu screen, theviewer operates the remote controller 11 a at hand to interactivelyselect one among the plurality of contents recorded on the DVD media M.In this example, “video 1” and “video 2” are viewing management targetcontents, and, with “video 1”, the viewer is able to select “withpreview” or “without preview”.

When the viewer, for instance, selects the item of “video 1 (withoutpreview)”, which is a viewing management target content, from thisactivation menu screen (STEP 203 of FIG. 2), the DVD player 11 displaysthe first viewer authentication screen associated with the selecteditem, and requests the viewer to enter the password (STEP 204).

FIG. 4 is a diagram showing an example of the first viewerauthentication screen according to the present embodiment. This firstviewer authentication screen is constituted by including a URL 41 forshowing the website to be accessed for acquiring the password, anacquisition code field 42 showing the acquisition code required inacquiring the password, and a password input field 43 to which thepassword is to be input. In other words, the DVD player 11 dynamicallyand internally generates an acquisition code based on the disc controlinformation of the DVD media M and according to the execution proceduresprescribed therein, displays the first viewer authentication screenincluding the generated acquisition code, and requests the input of thepassword corresponding to the acquisition code.

In order to generation this acquisition code, for example, as shown inFIG. 5, a password management table which associates the password andacquisition code is registered in the DVD media M. Meanwhile, the servercomputer 2 has a viewing management database containing a table with thesame contents as this password table for conducting viewing managementemploying this acquisition code.

The DVD player 11 generates a prescribed random number with the randomgenerated function, which is an internally incorporated function,according to the execution procedures prescribed in the disc controlinformation, reads the acquisition code corresponding to such randomnumber from the password table, and, as shown in FIG. 4, displays anacquisition code display field 42 of the first viewer authenticationscreen.

In a state where this first viewer authentication screen is beingdisplayed, the viewer uses the mobile telephone 13 to access the websiteindicated by the URL 41 of the first viewer authentication screen, andacquires the password via the required viewer authentication.Incidentally, the password acquisition processing will be describedlater.

When the viewer acquires the password via the prescribed operationprocedures from the prescribed website, the viewer operates the remotecontroller 11 a to input the password in the password input field 43 ofthe first viewer authentication screen, and, for example, pushes theselect button (STEP 205 of FIG. 2). When the DVD player 11 receives thepassword from the viewer, it compares this with the passwordcorresponding to the acquisition code specified previously with therandom number registered in the password table, and judges whether thetwo passwords coincide (STEP 206). When the DVD player 11 judges thatthe password input from the viewer coincides with the passwordregistered in the password table; that is, when it judges that the inputpassword is valid, a flag showing the success of authentication isstored in the internal memory buffer, and the reproduction of thecontent is started according to the disc control information (STEP 207).As a result, the viewer will be able to view the viewing managementtarget content that he/she wished to view. Here, it is preferable thatthe flag showing the success of authentication is stored in the internalmemory buffer for each content since viewing will be managed for eachviewing management target content.

Incidentally, when the DVD player 11 judges that the input password isnot valid, it performs prescribed error processing (STEP 208), andcompulsorily ends the processing. Here, instead of compulsorily endingthe processing, the process may return to the activation menu screen.

FIG. 6 is a flowchart for explaining the flow of password acquisitionprocessing according to the present embodiment. This passwordacquisition processing, as described above, is conducted between themobile telephone 13 and server computer 2.

As shown in FIG. 6, when the viewer utilizes the Internet connectionfunction of the mobile telephone 13 and accesses the website indicatedby the URL 41 on the first viewer authentication screen; that is,accesses the server computer 2, the server computer 2 will respondthereto by displaying on the display unit of the mobile telephone 13 aviewer authentication screen on the mobile telephone side (hereinafterreferred to as the “second viewer authentication screen”) (STEP 601).FIG. 7 is a diagram showing an example of the second viewerauthentication screen according to the present embodiment. Here, whenreproducing the viewing management target content, it is necessary thatthe viewer be registered in advance as a member of the media providerthat is providing such DVD media M. Thus, when the viewer has not yetperformed member registration, the viewer will select the “new” button71 on the second viewer authentication screen to conduct memberregistration procedures (STEPS 602 and 603). As a result of the memberregistration procedures, the viewer will be assigned a viewer ID andpassword, and be registered in the database system of the servercomputer 2. Incidentally, in order to realize the charging processing tothe viewer, for example, an effective credit card number or the like maybe deposited. As this kind of member registration procedure/chargingmethod, various publicly known methods may be employed, and theexplanation thereof is omitted.

When the viewer inputs the ID and password that were personally assignedon the second viewer authentication screen, the mobile telephone 13transmits the input contents to the server computer 2. The servercomputer 2 performs authentication based on the ID and password sentfrom the mobile telephone 13, and judges whether the viewer is aregistered member or not (STEP 604). When the server computer 2 judgesthat the viewer is a registered member, the server computer 2 displayson the display unit of the mobile telephone 13 an acquisition code inputscreen (STEP 605). Incidentally, when the server computer 2 is not ableto authenticate that the viewer is a registered member, it performsprescribed error processing and ends the routine (STEP 610).

FIG. 8 is a diagram showing an example of the acquisition code inputscreen according to the present embodiment. An acquisition code inputfield for inputting, for example, a 12 digit number is provided to theacquisition code input screen. When the viewer inputs the acquisitioncode in the acquisition code input field of the acquisition code inputscreen while referring to the first viewer authentication screendisplayed with the DVD player 11 and selects the OK button, the mobiletelephone 13 transmits the input contents to the server computer 2. Whenthe server computer 2 receives an acquisition code from an authenticatedmobile telephone 13, it refers to the viewing management databasesystem, specifies the contents and viewing conditions (viewing period,price, etc.) of the viewing management target content corresponding tosuch acquisition code, and displays on the display unit of the mobiletelephone 13 the viewing confirmation screen showing such items (STEP606). Specifically, the server computer 2 refers to the viewingmanagement database, and, foremost acquires the viewing period on theone hand, acquires the current date and time with the clock function onthe other, and judges whether the current date and time are within therange of the viewing period. And, when the server computer 2 judges thatthe current date and time are within the range of the viewing period, itgenerates a viewing confirmation screen according to the contents ofother fields in relation to the acquisition code, and sends this to themobile telephone 13.

FIG. 9 is a diagram for explaining an example of the data structure ofthe viewing management database of the server computer 2 according tothe present embodiment. This viewing management database is used whenthe server computer 2 conducts the viewing management of contents forthe viewer.

As shown in FIG. 9, the respective records of the viewing managementdatabase, for example are constituted from the respective fields ofacquisition code 91, password 92, title 93, period 94 and price 95. Therespective fields of the acquisition code 91 and password 92 are thesame as the contents of the password table recorded in the DVD media tobe distributed or provided. The title field 93 shows the title of thecontent, and the period field 94 and fee field 95 show the viewableperiod (e.g., from when to when) and the viewing fee of the respectivecontents. In other words, from the perspective of the media provider, itis possible to comprehend the content from the acquisition code, andmanage the viewing period and viewing fee of such content.

FIG. 10 is a diagram showing an example of the viewing confirmationscreen according to the present embodiment. When the viewer selects theOK button on this viewing confirmation screen, for example, (STEP 607),the server computer 2 displays the password presentation screen asillustrated in FIG. 11 on the display unit of the mobile telephone 13(STEP 608 and 609). Here, the server computer 2 charges the viewer forthe viewing fee of such content.

Incidentally, as described above, when the DVD media M is ejected, theDVD player 11 will reset the authentication success flag stored for eachcontent in the internal memory buffer, and the viewer will be requiredto reacquire the password. Here, when the viewer requests for thereacquisition of the password during the viewing period in the servercomputer 2, it is preferable that the password presentation screen issimply provided, and charging processing is not performed again to suchviewer.

As described above, when the viewer uses the mobile telephone 13 andacquires the password, the user then inputs such password in thepassword input field 43 of the first viewer authentication screen.Thereby, the DVD player 11 will start the reproduction of the viewingmanagement target content.

As described above, according to the present embodiment, uponreproducing a specified content recorded on the DVD media M, the vieweruses the mobile telephone 13 to access the server computer 2 on theInternet and acquire the password with the acquisition code shown on thefirst viewer authentication screen, and is urged to input such password.Thus, even if it is a stand-along DVD player 11 that does not have anetwork connection function, it is possible to manage the viewing ofcontents.

The foregoing embodiments are exemplifications for explaining thepresent invention, and the present invention shall not be limited tosuch embodiments in any way. The present invention may be worked invarious forms so as long as the gist hereof is not deviated.

For example, in the present embodiment, although a mobile telephonehaving an Internet connection function was explained as an example of aportable information terminal device 13, this is not limited thereto.For example, when using an ordinary telephone, the acquisition code andpassword may be exchanged by conducting an audio-based interactiveoperation with an audio response system. Further, in the case of a settop box having an interactive function, the acquisition code andpassword may be exchanged with an interactive operation in relation to aspecified data broadcast program.

According to the present invention, provided is a viewing managementfunction in a simple manner while giving consideration to thecompatibility with existing visual reproduction devices.

1. A viewing management method for managing the viewing of media contentrecorded on an information recording medium readable with a prescribedreproduction device, said method comprising the following steps: saidprescribed reproduction device presenting an acquisition codeprerecorded on said information recording medium to a viewer desiring toview a viewing management target media content; said prescribedreproduction device receiving a password acquired by the viewer from aserver computer based on the acquisition code; and said prescribedreproduction device starting reproduction of said viewing managementtarget media content via an authentication process based on thepassword, wherein a password management table associating said passwordwith said acquisition code is prerecorded on said information recordingmedium, and the step of presenting the acquisition code occurs each timea media content reproduction request is received from the viewer andincludes: said prescribed reproduction device generating a random numberbased on a prescribed random function; and said prescribed reproductiondevice selecting and presenting an acquisition code corresponding to thegenerated random number from the password management table.
 2. A viewingmanagement method according to claim 1, wherein, when said vieweracquires the password from said server computer, a viewing fee of saidviewing management target media content is charged to said viewer.
 3. Aviewing management method for managing the viewing of media contentrecorded on an information recording medium readable with a prescribedreproduction device, comprising the following steps: said prescribedreproduction device starting to read said information recording medium;said prescribed reproduction device presenting a prescribed acquisitioncode to a viewer, and urging the viewer to input a prescribed password;a prescribed server computer accessed by an information terminal deviceof said viewer urging the viewer to input the prescribed acquisitioncode; said prescribed server computer presenting a passwordcorresponding to said prescribed acquisition code to said viewer uponreceiving said prescribed acquisition code from the information terminaldevice of said viewer; said prescribed reproduction device performing,upon receiving a prescribed password from said viewer, authenticationbased on the prescribed password; and said prescribed reproductiondevice starting reproduction of the media content recorded on saidinformation recording medium when it judges that the prescribed passwordis valid as a result of said authentication, wherein a passwordmanagement table associating said password with said acquisition code isrecorded on said information recording medium, and said prescribedreproduction device presents an acquisition code corresponding to arandom number generated according to a prescribed random function.
 4. Aviewing management method according to claim 3, wherein said servercomputer comprises a viewing management database containing a tablecorresponding to said password management table, and wherein aprescribed password corresponding to the prescribed acquisition codereceived from the information terminal device of said viewer isspecified by referring to said viewing management database, and theprescribed password is presented to said viewer.
 5. A viewing managementmethod according to any one of claims 3 or 4, wherein a URL foraccessing the server computer is recorded on said information recordingmedium, and said prescribed reproduction device presents said prescribedacquisition code together with said URL.
 6. A viewing management methodaccording to claim 3, wherein said viewing management method furthercomprises a step of urging said viewer to select a viewing managementtarget media content, and when said viewing management target mediacontent is selected, the prescribed acquisition code corresponding tosaid selected viewing management target media content is presented.
 7. Asystem for reading an information recording medium with a prescribedreproduction device, the system comprising: a prescribed reproductiondevice; and an information recording medium having recorded thereon aviewing management target media content, a prescribed passwordmanagement table and prescribed control information, wherein in saidprescribed password management table, a prescribed password isassociated with a prescribed acquisition code, and wherein saidprescribed control information contains a control program for saidprescribed reproduction device to be capable of performing a pluralityof functions, the functions comprising: said prescribed reproductiondevice presenting a prescribed acquisition code corresponding to arandom number generated according to a prescribed random function tosaid viewer and urging said viewer to input a prescribed passwordassociated with said presented prescribed acquisition code in saidprescribed password management table, said prescribed reproductiondevice performing authentication of said input prescribed password whensaid viewer inputs said prescribed password, and said prescribedreproduction device reproducing said viewing management target mediacontent according to the result of said authentication.
 8. A viewingmanagement method according to claim 3, wherein said server computercomprises a viewing management database containing a table correspondingto said password management table, said table associating saidacquisition code with said password, a title of said media content, aperiod during which said media content is available, and a fee forviewing said media content.
 9. A system according to claim 7, whereinsaid prescribed server computer comprises a viewing management databasecontaining a table corresponding to said password management table, saidtable associating said acquisition code with said password, a title ofsaid media content, a period during which said media content isavailable, and a fee for viewing said media content.